The effect of different promoters on activity and selectivity of Lewis-acidic chloroaluminate ionic liquid catalysts was studied for isobutane/2-butene alkylation. When tert-butyl halides are used as promoters, the active species of the alkylation reaction, which is the tertbutyl cation, is directly generated whereas upon catalysis with Brønsted-acid supported ionic liquids, this species is indirectly provided through a hydride shift between protonated 2-butene and isobutane. Experimental results both from batch and continuously operated liquid phase alkylation reactors indicate, that tert-butyl halides are able to speed up the reaction rate significantly and shift the C 8 -selectivity towards the desired high-octane trimethylpentanes (TMPs). However, secondary reactions like oligomerization and cracking could not be suppressed by the use of this additives and high deactivation rates in continuous opperation were observed. Suggestions are made, how the product composition is effected by the additive and how the promoted IL-catalyst system is deactivated with time on stream.

In isobutane/2‐butene alkylation, chloroaluminate ionic liquid catalysts (CAIL) deactivate fast with time on stream with respect to activity and selectivity. Hence, the effect of anhydrous hydrogen chloride (HCl), which shows co‐catalytic behavior, was studied in a batch reactor and its effect on both parameters was investigated. The co‐catalyst leads to an increased reaction rate and improves the yield of trimethylpentanes, the primarily desired high‐octane compounds of alkylation. Moreover, already deactivated CAIL catalysts are reactivated by gaseous HCl. In addition saturation of the ionic liquid with HCl prior to the reaction effectively suppresses the deactivation of the CAIL catalyst. Thus, the solubility of hydrochloric acid is reported for both the CAIL (IL: [BMIM]Cl/AlCl3, x AlCl 3=0.64) and organic phase to gain a deeper understanding of the reaction system. Finally conjunct polymers dissolved in the ionic liquid were extracted to study their influence on deactivation.

The kinetics of the IL-catalyzed reaction of isobutane with 2-butene and the size distribution of the dispersed IL droplets were investigated in a stirred tank reactor. The results were used to calculate the intrinsic reaction rate constant with a model accounting for the interplay of external and internal mass transport and chemical reaction. The intrinsic reaction rate was found to be very high, leading to a low effectiveness factor of the IL catalyst. The used fraction of the IL droplets with a diameter of about 400 μm was very small, and the actual reaction took place only in a thin spherical shell with a thickness of about 5 μm.

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The reaction between glucose and mcthylcne blue, catalyzed by glucose oxidase (GOD), was analysed calorimetrically. The amount of heat produced under saturating methylene blue concentrations (> 10-2 mol/l) was measured with glucose concentration and time as parameters (kinetic procedure). Kinetic constants (pseudo one substrate kinetics) were derived from tho experimental data: K M (~~~~~~~) = 1.18x 10-3 mol/l and T, , , = 0.085 J/mg GOD min (3.89 . lo-" mol/mg GOD min).Comparison of caloric with optical measurements gave an enthalpy of reaction of 22.52 kJ/mol. Considering the observed substretc inhibition, glucose determinations arc possible up to glucose concentrations of 0.1 mol/l. ZussmmonfassungDie G1 ukoseoxydase-kstalysierte Reaktion zwischen Glukose und Methylenblau wurde kalorimetrisch verfolgt. Die unter siittigenden Methylenblaukonzentrationen (> lo-* mol/l) gebildeten Warmemengen mirden mit Glukosekonzentration und Zeit als Parametern bestimmt (kinetisches Verfahren). Die Experimente ergaben folgende kinetische Daten (Pseudo-Einsubstratkinetik) : KM(Glukose) = 1,18 . 10-3 mol/l und V,,, = 0,085 J/mg GODmin (3,89 -10-6 mol/mg GODmin).Der Vergleich der kalorischen mit optischen Messungen ergab eine Reaktionsenthblpie von 22,52 kJ/mol. Unter Berucksichtigung der beobachteten SubstratuberschuBhemmung sind Glukosebestimmungen bis zu 0,l mol/l moglich.

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Es wurden stabile w/o-Mikroemulsionen aus wässriger Phase, Cyclohexan und verschiedenen Tensiden der Marlipal O13-Reihe erzeugt und darin via chemischer Reduktion metallische Nanopartikel generiert. Dies erfolgte sowohl über die 2-Emulsionstechnik als auch mittels direkter Reduktionsmittelzuga-